On the Al Jazeera television network, an overbearing host was grilling Julian Assange, one of the founders of WikiLeaks, the online drop zone for whistleblowers.

Assange, an Australian who rarely makes public appearances and shuffles around the world with little more than a rucksack and a laptop, quickly dealt with his haughty inquisitor. Lean and tall with a handsome, distant face, long grey locks and dressed in a a dark suit, Assange, in his late 30s, is a commanding presence.

He has a deep broadcaster's voice and gave measured, drum-tight answers about the blow he had just dealt the US military with WikiLeak's release of footage of an American helicopter gunship killing Iraqi citizens and two Reuters journalists on a Baghdad street in July 2007.

The video, shot from the helicopter, includes the voices of soldiers urging a gravely wounded Reuters photographer to pick up his weapon (they apparently did not realise it was a camera) so he could be lawfully finished off with the aircraft's deadly 30mm cannon. When a beaten-up van slithers to a halt and its passer-by occupants tumble out to aid the wounded, they too are gunned down. Only two maimed children survive.

It becomes clear why the military has resisted the demands of Reuters and others for the release of the video; the military had long claimed it did not know how the Reuters journalists had died and it initially withheld the fact that children were present.

Assange resisted Al Jazeera's invitation to savage US authorities for their years of dissembling, remarking simply: ''There was certainly spinning the message and it does seem like there has been a cover-up.''

He didn't need to say more; by week's end the video had been viewed 4.8 million times. Its impact upon the reputation of US servicemen in Iraq is devastating. Another US military video - showing last year's bombing of Afghan villages as they siphoned fuel from a tanker hijacked by the Taliban - is also coming to WikiLeaks.

Clearly someone inside the military has begun leaking, elevating WikiLeaks and Assange overnight from mainstream journalism's fringes to a must-see news breaker. ''This is a whole new world of how stories get out,'' declared Sree Screenivasan, a professor of digital media at the Columbia University journalism school in New York.

Yet for all its ideals in support of openness and freedom of information, those behind WikiLeaks - especially its key founder, Assange - dwell in shadows and intrigue.

They have no headquarters, no offices and the barest of a formal structure. Assange is particularly elusive, part obviously through necessity and part mercurial make-up. Home - or the nearest he has to one - is said to have been eastern Africa for the past two years or so.

He has rarely spoken of his upbringing in Australia or life outside of his work, arguing that to do so may assist those who want him and WikiLeaks silenced.

But the trail of his life is across the internet, as coded and mysterious as the man he is today. It begins - publicly at least - in October 1991 when Assange, then a teenager, was charged with 30 computer hacking offences.

Prosecutors alleged he and others hacked the systems of the Australian National University, RMIT and Telecom. They had even managed to remotely monitor the Australian Federal Police investigation into their activities, Operation Weather.

Assange admitted 24 hacking charges and was placed on a good behaviour bond and ordered to pay $2100. The investigation in Australia began after an audacious attack on NASA's computers in 1989.

The word ''WANK'' appeared in big letters on NASA monitors, an acronym for Worms Against Nuclear Killers. Underneath was an Australian connection - lines from a Midnight Oil song. Whoever did it was never identified.

In 1997 an astonishing book was published in Melbourne. It sold a respectable 10,000 hard copies but, when it was made available free on the internet it was downloaded 400,000 times within two years.

Underground told the riveting inside story of the city's computer hackers and Assange was prominently billed in it as a researcher for the book's author, Dr Suelette Dreyfus, now an academic researcher. It opened with a detailed account of the NASA attack.

Dreyfus wrote glowingly of Assange's efforts: ''Julian had worked thousands of hours doing painstaking research; discovering and cultivating sources, digging with great resourcefulness into obscure data bases and legal papers - not to mention providing valuable editorial advice.''

The book did not name the Melbourne hackers but used their online identities and told their story. The records of Assange's court case and his biographical details on WikiLeaks match the story of Mendax - one of the hacker's online identities in Underground. ...

For his epigraph in the online edition of Underground, Assange used an Oscar Wilde quote: ''Man is least himself when he talks in his own person. Give him a mask, and he will tell you the truth.''

Thanks Gav - I read this book a long time ago and could never find it again. It is really interesting reading now I can download it on my iPhone from Stanza. What would Electron have done with an iPhone?